Regenerative fuel pumps have been used for years in automotive fuel supply applications. Conventional automotive fuel pumps typically have a rotary pumping element, such as an impeller, that is encased within a pump housing. Typical impellers have a plurality of vanes and ribs formed around the periphery of a central hub. Rotation of the impeller draws fuel into a pumping chamber located within the pump housing. The pumping action of the impeller causes fuel to exit the fuel pump housing at high pressure. Regenerative fuel pumps are commonly used in automotive applications because they produce a more constant discharge pressure than other types of pumps. They also typically cost less and generate less audible noise during operation than other known pumps.
Pump efficiency and noise are two characteristics that are considered important when designing a fuel pump impeller. Staggered vane impellers have been used to provide lower pressure pulsation and noise, at the sacrifice of pump efficiency. Staggered vane impellers utilize a first row of vanes on the cover side of the impeller and a second row of vanes on the body side of the impeller. The first row of vanes are staggered relative to the second row of vanes. Partition or connecting walls may be utilized between staggered vanes.